using System; 

using System.Linq; 

using System.Text.RegularExpressions; 

using System.Diagnostics; 

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Parsing string '123as456'\n"); 

        Stopwatch sw = new Stopwatch(); 

        sw.Start(); 

        //regex get all numbers

        Console.WriteLine(string.Format("{0:00} regex split all numbers", string.Join(null,Regex.Split("123as456", "[^\\d]"))));

        sw.Stop(); 

        Console.WriteLine(string.Format("                               ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

        sw.Restart(); 

        //regex get all numbers 

        Console.WriteLine(string.Format("{0:00} regex replace all numbers", Regex.Replace("123as456", @"\D","")));

        sw.Stop(); 

        Console.WriteLine(string.Format("                               ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

        sw.Restart();

        //regex get 1st numbers

        Console.WriteLine(string.Format("{0:00} regex match 1st number", Regex.Match("123as456", @"^\d+").ToString())); 

        sw.Stop(); 

        Console.WriteLine(string.Format("                           ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

        sw.Restart();           

        //regex get last number

        Console.WriteLine(string.Format("{0:00} regex match last number ", Regex.Match("123as456", @"\d+$").ToString())); 

        sw.Stop(); 

        Console.WriteLine(string.Format("                           ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

        sw.Restart();

        Console.WriteLine("Parsing string '222star10bucks'\n"); 

        //linq all numbers in a string successively 

        Console.WriteLine( 

            string.Format("{0:00} linq select all numbers where long format", 

               new string(

                         (from t in "222star10bucks"

                          where char.IsDigit(t)

                          select t).ToArray()

                         )

                         )

                         );

         sw.Stop(); 

         Console.WriteLine(string.Format("                                              ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

         sw.Restart();

         //linq all numbers in a string successively 

         Console.WriteLine(string.Format("{0:00} linq where digits all numbers", new String("222star10bucks".Where(Char.IsDigit).ToArray()))); 

         sw.Stop(); 

         Console.WriteLine(string.Format("                                  ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

         sw.Restart();

         //linq 1st number in a string          

         Console.WriteLine(string.Format("{0:00} linq takewhile 1st number", new String("222star10bucks".TakeWhile(Char.IsDigit).ToArray()))); 

         sw.Stop(); 

         Console.WriteLine(string.Format("                              ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

         sw.Restart();          

         //linq last number in a string, must end in a number

         Console.WriteLine(string.Format("{0:00} linq reverse takewhile last number", string.Concat("222star10".ToArray().Reverse().TakeWhile(char.IsNumber).Reverse())));

         sw.Stop(); 

         Console.WriteLine(string.Format("                                  ﹂ in {0} ticks",sw.ElapsedTicks.ToString("N0"))); 

    }

}